1. Field of the Invention
The invention relates to a method for selecting an operation channel, more particularly to a method and a channel selector that are configured to automatically select a channel with an optimal channel quality for operation, and to a wireless network connecting apparatus that includes the channel selector.
2. Description of the Related Art
Direct sequence spread spectrum (DSSS) is a modulation technique that is typically employed in wireless communications through an unlicensed 2.4 GHz industrial scientific medical (ISM) band. Examples of communications that use DSSS include a wireless universal serial bus (USE), IEEE 802.11b/g/a specification (commonly known as wireless fidelity, or Wi-Fi), and IEEE 802.15.4 specification (commonly known as ZigBee).
It is known that the Wi-Fi and ZigBee specifications have different yet complementary characteristics. Compared to the Wi-Fi specification, ZigBee specification offers short-range wireless transfer of data at relatively low transmission rate, but comes more preferable in terms of complexity and costs. Thus, there has been a growing need for allowing Wi-Fi and ZigBee co-existence. For example, a multi-interface wireless device, such as a Wi-Fi-ZigBee bridge, has been developed to enable communication using both specifications simultaneously.
However, since both communications operate on an identical band, it may be possible that communications using the two specifications may operate on overlapping channels. This may result in interference between the data transmissions and subsequent occurrence of data retransmissions. Subsequently, the overall transmission efficiency is reduced, and longer transmission time leads to power waste.